Selection against Recessives and Its Effect on Inbreeding in Self-pollinating Plants

Abstract

The selfing system of inbreeding occurs in both natural and artificial populations. In the extraction of inbred lines in cross- and often-cross-pollinated species, like corn and sorghum, selfing is used along with the selection process (either by nature or by the breeder). The inbreeding coefficient in the population may not be as high as expected, especially when selection is against the homozygotes. On the other hand, if selection is against the heterozygotes, then the inbreeding coefficient can be higher than expected. This fact also holds for strictly self-pollinated species.